AddAttachment Help Attachments Don't Upload

I have a custom list and form for that interacts beautifully with Sharepoint...the only issue is that I cannot get attachments to uplaod. Can somebody please help me - I have been working on this for a few days and have reached an impass. I have
tried multiple things and I am new to SPwebservices. I am developing in vs2010 for MOSS, .Net 3.5 . Thank you in advance!